From the related art, an inkjet printer is known (for example, JP-A-2008-213162) which includes a detachable main tank, a sub tank that stores ink supplied from the installed main tank, and an image recording unit that jets the ink stored in the sub tank and prints an image. In the inkjet printer having the above configuration, internal spaces of the main tank and the sub tank are opened to the air. For this reason, when the main tank is installed in the inkjet printer, the ink moves due to a water head pressure so that the liquid level of the main tank and the liquid level of the sub tank are aligned with the same height by the difference between a water head in the internal space of the main tank and a water head in the internal space of the sub tank (hereinafter, referred to as “water head difference”).
Even when the main tank is not installed in the device, if ink is stored in the sub tank, the ink is supplied from the sub tank to the image recording unit, whereby it is possible to execute image recording by the image recording unit. However, depending on the presence or absence of the main tank, the flow path resistance when the ink flows from the sub tank to the image recording unit varies, so that the supply of ink to the image recording unit may be insufficient. As a result, jetting failure of the ink from the image recording unit occurs, and the quality of the recorded image may deteriorate in some cases.